高温高密度等离子体辐射源产生脉冲X射线的同时还产生等离子体碎片，飞散速度分布在0.1~10 km/s。研制电磁驱动超高速机械快门，有效通光孔径为40 mm×50 mm，利用45 mm×60 mm×100 μm的铝膜作为快门叶片，在放电电压20 kV、驱动电流80 kA、放电周期18 μs条件下，获得的快门关门时间小于180 μs。将快门放置在距离等离子体X射线源2 m处， X射线通过后在180 μs时间内关闭光学通道，以阻挡高温高密度等离子体产生的碎片，保护X射线精密探测系统和样品，同时实现等离子体参数的精密测量。

A radiation simulator utilizing plasma radiation sources will generate large amount of undesirable debris which can potentially damage the frangible diagnosing detectors and the objects under test. An electromagnetically driven fast shutter for purpose of debris mitigation is developed, which erects a physical barrier to slow down the moving debris after allowing the passage of X-ray photons. The shutter system consists of a pair of thin metallic foils twisting the parallel axes, which is imploded by an outer magnetic field generated by a fast capacitor discharging into a single turn loop. Typical capacitor bank charging voltage is 20 kV, with a corresponding current of 80 kA and a discharging current period of 18 microseconds. A closure time as fast as 180 microseconds is observed with the effective cross-sectional area of 40 mm×50 mm. The design and operation of the shutter system are described along with the measured results of closure times.